The disease process known as osteoarthritis or degenerative joint disease as identified by radiologic and pathologic criteria represents a broad clinical spectrum with varying rates of progression from one patients to the next. Biochemical analysis of cartilage from patients with this diagnosis may show heterogeneity among patients and within different locations of the same joint having similar histologic appearance. This study proposes to perform biochemical studies on cartilage and synovium from patients with osteoarthritis and correlate this data with prospective clinical parameters such as age, duration of disease, work history, rate of progression, drugs, etc. All patients undergoing hip and knee reconstructive surgery for osteoarthritis or allied disorders will have preoperative questionnaires completed. Specimens of articular cartilage from these patients will be studied in vitro using isotopic sulfate, glucosamine, or serine to evaluate structure and synthesis of proteoglycan aggregation, monomers, glycosaminoglycans, link protein, and hyaluronate. Synovial specimens will be studied for lysosomal enzymes and hyaluronate synthesis using isotopic glucosamine. The proposed studies hope to answer two questions. Does the biochemical heterogeneity in human articular cartilage represent different disease or different rates of progression of the same disease? Secondly, is there a difference in biosynthesis of proteoglycans in diseased articular cartilage, and if so, is the difference in synthesis or breakdown of glycosaminoglycans, intact proteoglycans, or assembly of aggregated complexes?